This project involves the synthesis of 3-cyano-2-azetidinones, a class of Beta-lactams which show antibiotic and antifungal activity. The general synthetic routes to these compounds include the cycloadditions of cyanoketenes to imidates and imines as well as the ring contraction of 4-azido-2-pyrrolinones. Both of these routes proceed via zwitterionic intermediates and these are also under study as potentially useful precursors to other heterocyclic compounds. The biologically active species is also believed to be zwitterionic species formed by an electrocyclic ring opening of the Beta-lactams. Thus, a study of this ring-opening reaction is also under investigation.